Ion valve for producing alternating currents



June 18, 1935.

Filed July 7, 1933 2 Sheets-Sheet, 1

flare/flops. K amll m 145 rzlkssozz,

June l8, 1935.

K. E. ERIKSSON Er AL 2,005,458 ION VALVE FOR PRODUCING ALTERNATING CURRENTS Filed July 7, 1935 2 Sheets-Sheet 2 F195 1 296 /5 5/ F L I 1 5:

Ja e/120115 Karl Z'rZkZrZ/assom U20 Lam/n M. My

frequency,

Patented June 18, 1935 ION VALVE FOR assignors poration of Sweden Application July 7, 1933, Serial No. 679,343 In Sweden July 8, 1932 In ion valves using metal 7 Claims.

vapor or inert gas direct current or alternating the transfer of the current current of another it has been already proposed to effect from one anode to another by applying a voltage to the latter, either by impressing on the alternating current side a master voltage from a machine or the like, or

by temporarily introducing a first and the second anode voltage between the at the instant of transfer. The present invention relates to another method of effecting the current transfer which in many cases gives ment, namely by means of (transition anode) which is to a simpler arrangean auxiliary anode mporarily subjected to a voltage varying in such way as to cause said anode to take over first the arc from the previously burning anode and then deliver it to the next main anode.

In the accompanying drawings, Fig. 1 shows diagrammatically one form of the invention and Fig. 2 a time diagram of its manner of operation. Figs. 3-7 show diagrammatically six other forms of the invention.

Referring to Fig. 1, I designates a source of direct current, the negative pole of which is connected to the common cathode l3 of an ion valve while its positive pole is connected over an inductance coil l4 and the two halves of a transformer Winding l5, IE to the two main anodes 5,

6 of the ion valve. The secondary winding ll of the transformer is connected to the alternating current network 2. scribed is substantially The arrangement so far deknown. According to the present invention, the positive pole of the direct current source is transition anode 4 over a voltage 3 which is adapted to also connected to a separate source of create an alternating voltage of substantially the type shown in Fig. 2. At the instant intended for extinguishing the anode 5, a positive voltage is thus impressed on the transition anode 0 so as to make its potential with respect to the cathode. higher than that of the anode 5. The are is then transferred from the anode 5 to the anode 4, and the impressed voltage should be sufficient for covering all voltage drops caused by the normal current in the circuit of said tain the normal current the cathode. The transition latter anode so as to mainbetween said anode and anode 4 should also be so designed in respect of cooling etc. as to be able to carry the normal current during a short transitory period. As the anode 5 is normally blocked by an appropri ate negative voltage PRODUCING ALTERNATING CURRENTS Karl Erik Eriksson Sweden,

triska Aktiebo being applied to its control grid 25 from a battery 40, it cannot be reignited after once being extinguished. At an appropriate instant, substantially coinciding with that in which the additional voltage on the auxiliary'anode 4 is changed from a positive to a negative value (Fig. 2) the normal blocking of the anode 6 is suspended by a positive voltage being impressed on its grid 25 from the battery 40 over a contact apparatus hav-' ing rotating contacts 4|, 42 and stationary contacts 43, 46; The auxiliary anode 4 will then have a lower total voltage than the anode 6, and the arc will be transferred to the latter. During the next .semicycle the procedure will 'be the inverse of that described, so that the arc is transferred 15 from the anode 6' over the anode 4 to' the anode 5 as the blocking of the latter is suspended by a positive voltage being applied to its grid over the stationary contact 45. It is generally advisable to use a blocking grid 21 also for the anode4 and to suspend the blocking thereof shortly before that of the anodes 5 and 6 'by means of contacts 44, Maon the-contact-apparatus.

In Fig. 3, the additional voltage on the transition anode 4 is obtained by means of a condenser 25 I which is charged over a switch 8 from a source of direct current S). An inductance coil l8 shown in dotted lines may facultatively be connected in series with said switch.

In Fig. 4, the switch 0 is replaced by a grid- 30 controlled electric valve l2, and further a separate direct current source for charging the condenser has been made superfluous by'introducing an inductance Hi. When the condenser is discharged to the transition anode 4, the voltage on 30 its lower conducting layer must sink below that of the upper one in order to cause the anode 0 to take-over the current. If the valve 12 is released after the current through the anode 4 has been broken, a charging current therefore flows to the lower conducting layer of the .condenser, and thanks to the inductance 10 this current will continue until the lower layer has been positively charged, that is, has obtained a higher potential than the positive pole of the direct current source. The action can be regulated by connecting an inductance ll between the condenser and the transition anode.

If the condenser l is connected not directly but inductively to the transition anode 4 accord- 0 ing to Fig. 5, the valve 12 for charging the condenser may form part of the main apparatus, that is, consist of a separate anode l2 therein having a separate grid control 22. The transformer for connecting the two circuits together 55 ing currents, in which case one transition anode may be common to all phases or to certain phases. They may also be used for frequency conversion. Two examples of such arrangements are shown in Figs. 6 and '7. In Fig. 6, the primary alternating current is supplied to the Y-connected primary winding of a transformer 3|, the Y- connected'secondary winding of whichis connected with its neutral point to the cathode l3 of the ion valve and with the phase terminals to the midpoints of the two primary windings of the secondary transformer 32. The outer terminals of said last-mentioned windings are connected to the main anodes 35 and their midpoints over the transformer IQ of a condenser circuit 1, l0, I2, arranged in analogy with Fig. 5, to the transition anodes 34. Several such condenser circuits may be provided instead of a common one.

Fig. 7 differs from Fig. 6 substantially in that the secondary winding 32 has only one primary winding each half of which is connected to three windings 3| of the primary transformer, one for each phase, with corresponding anodes. In connection herewith, each phase has one .winding for connection to the transition anode 34. The condenser circuit for producing the voltage on the latter is practically analogous to that of Fig. 6.

'We'claim as our invention:-

, 1'. In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, and a'transition anode combined with means for impressing a transitory voltage thereon sufficient to cause said transition anode to absorb the load current from one main anode and deliver same to the next anode.

. 2. In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and means connected in series with said auxiliary anode for impressing a voltage suflicient to cover the voltage drop caused by said temporary current load.

3. In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and a condenser and a source of current connected between said auxiliary anode and the cathode.

4:- In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and a source of current, an interrupting device, and a condenser connected between said auxiliary anode and the cathode. V

5. In ion valves for producing alternating cur rents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and a source of current, a condenser and an electric valve connected between said auxiliary anode and the cathode.

6. In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current .to said'cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and a source of current, a condenser, an inductance, and an electric valve connected between said auxiliary anode and the cathode.

7. In ion valves for producing alternating currents, a cathode, a plurality of working anodes adapted to conduct alternatingly the current to said cathode, control grids for said anodes, means for impressing on said grids control voltages for blocking said anodes during certain intervals, an auxiliary anode adapted to carry said current during short time intervals, and a source of current connected in parallel with a condenser between said auxiliary anode and the cathode. KARL ERIK ERIKSSON.

UNO LAMM. 

